Substance abuse is a major public health problem associated with destructive or life-threatening outcomes in adolescents. Many substance abusing adolescents present with one or more co-morbid mental disorders, of which one of the most common is depression. In developing effective psychosocial substance abuse treatments, therefore, it is necessary to address co-morbid disorders. Studies of social cognitive and family characteristics, prevention and treatment suggest that cognitive behavioral interventions may be effective in the treatment of depressed, substance abusing adolescents. The first specific aim of this project is to develop and to operationalize in manuals a combined Group Cognitive Behavior Therapy (GCBT) and Family Cognitive Behavior Therapy (FCBT) for depressed, substance abusing adolescents. The second aim is to demonstrate the feasibility of conducting combined GCBT and FCBT with these adolescents and to provide pilot data for a subsequent, controlled outcome study. The third aim is to demonstrate the feasibility of training substance abuse counselors and therapies in the use of this treatment. The forth aim is to evaluate change in substance abuse and depression during treatment. To accomplish these aims, a ten step sequence of manual development and pilot testing is proposed. In the first year, initial manuals will be developed, based on literature review and consultation. In the second year, the Principal Investigator and Co-Investigator will treat six cases, with videotape supervision and expert consultation. After further manual revision, substance abuse counselors and therapists will be trained in year two and will conduct supervised treatment of 12 cases in year three. Treatment will consist of 16 weeks of GCBT and FCBT. Diagnostic interviews and self-report measures will be completed before and after treatment. Data analyses will address treatment integrity, patient satisfaction, and changes in diagnostic status, self-reported substance abuse and depression, and social cognitive and family variables. To plan a subsequent outcome study, power analysis will be used. Pilot data will include patient characteristics, compliance, attendance, and attrition rates.